By means of the developed technique a comparison of dynamic qualities of the track vehicle with usual and with the combined power installation containing an internal combustion engine and the flywheel energy storage is carried out. The assessment of influence of parameters of the combined power installation on dynamic qualities of the vehicle with mechanical transmission is executed. The factors limiting efficiency of action of combined power installation in the course of dispersal of the track vehicle are established. The received results allow to determine laws of management by the drive of a flywheel and to perform their optimization.